Follicle stimulating hormone (FSH) is a hormone synthesised and secreted by gonadotropes in the anterior pituitary gland. In the ovary FSH stimulates the growth of immature follicles to maturation. As the follicle grows, it releases inhibin which shuts off the FSH production.In men, FSH enhances the production of androgen binding protein by the Sertoli cells of the testes and is critical for spermatogenesis.